It was reasonable for Texas to opt out of the new "Common Core" standards for English and math that 45 other states have embraced. It was up to each state to decide for itself, and Texas had (and today still has) strong standards of its own in English, decent ones in math, solid assessments and a forceful results-based accountability system.

That system includes requiring kids to pass the tests and meet the standards in order to graduate, a tough but essential proviso that other states (including top-scoring Massachusetts) have found to be key to actual achievement gains.

Texas also has a "default" high school curriculum designed to prepare students for college-level work and modern careers - the kind with futures. Implemented properly (including elementary and middle schools that prepare youngsters for these high school rigors), the Lone Star State has embarked on an education regimen that will truly deliver the results that a 21st century economy requires and which individuals need to succeed in that economy.

All of which will start to unravel - and return Texas to an era of educational mediocrity - if Gov. Rick Perry ends up signing the ill-conceived rollback measure that cleared the House March 27.

Instead of today's "4 x 4" default curriculum, the norm for Texas teens would become an easier "foundation diploma" with 13 required courses.

Not such a big deal, you say? More insidious is that, by also scrapping 10 of the state's "end of course" exams, Texas essentially forfeits uniform academic expectations and goes back to the day when individual districts decided which students get diploma credit for which classes.

That means standards will (again) vary widely and neither employers nor colleges can be sure what knowledge and skills applicants truly possess. High school transcripts will be inscrutable and diplomas ambiguous. And because districts will be tempted to offer only the courses that the state requires, lots of young Texans - most of them likely poor or minority - will be left with little or no access to classes that would do the most to propel them to success in college and beyond.

No wonder major employers and university leaders oppose this measure.

Yes, 15 end-of-course exams may have been too many. But five is too few, especially in a state that has chosen to shun the comparable assessments into which most of the country is heading. Without standard measuring sticks, districts are apt (there's much evidence on this) to put rigorous-sounding labels on easy courses - in essence, faking it. Statewide end-of-course exams are the best way to discourage this.

Much recent debate in Texas has focused on whether every high school student needs to pass "advanced algebra." Yes, if one wants to enroll in college-level math without "remediation." But no, not every college student needs to take more math and not every high school student aspires to college.

Indeed, the nationwide "college for everybody" push has gone too far. But in today's economy, even young people headed for industry need serious math. It's irresponsible not to give all of them such career options - and irresponsible also to suppose that 16-year-olds are in the best position to make lifetime decisions.

Yes, they - with the assent of parent and guidance counselor - should be able to opt out of such courses. But the default should assume that everyone otherwise takes them. And the state assessment system should provide evidence that the courses are real, not fancy titles affixed to soft content that might be easy to pass in the short run but won't get credit from the real world in the long run.

The bill that cleared the House did make one improvement: a revamped accountability system will give individual schools parent-friendly letter grades from A to F rather than using complex terminology to designate a school's status. And academic achievement will continue to figure in those designations. The problem is that bobtailing the assessment system means far less information will be available to determine how much achievement is actually occurring.

I hope, for the sake of millions of school kids in America's second most populous state - and for that state's future - that the Legislature sets this right before it reaches Perry's desk.

So many worthy education reforms are in play in Austin today, reforms that add up, if wisdom prevails, to a needed comprehensive overhaul of Texas K-12 education, that it would be a particular pity if the quality standards that should undergird everything else are themselves badly weakened.